Howtosignalprocessing
Answer : Aliasing occurs when an oscilloscope does not sample the signal fast enough to construct an accurate waveform record. The signal frequency is misidentified, and the waveforms displayed on an oscilloscope become indistinguishable. Aliasing is basically a form of undersampling.
- What is the cause of aliasing?
- Under what conditions does aliasing occur?
- How does aliasing occur in sampling?
- Does aliasing occur at the Nyquist rate?
What is the cause of aliasing?
Aliasing is Caused by Poor Sampling
A bandlimited signal is one with a highest frequency. The highest frequency is called the bandwidth ωb . If sample spacing is T, then sampling frequency is ωs =2π/T.
Under what conditions does aliasing occur?
Aliasing errors occur when components of a signal are above the Nyquist frequency (Nyquist theory states that the sampling frequency must be at least two times the highest frequency component of the signal) or one half the sample rate.
How does aliasing occur in sampling?
Aliasing occurs when a signal is sampled at an insufficient rate. Two different signals can become indistinguishable from each other when they are sampled – they are aliases of each other.
Does aliasing occur at the Nyquist rate?
When a component of the signal is above the Nyquist, a sampling error occurs that is called aliasing. Aliasing “names” a frequency above Nyquist by an “alias” the same distance below Nyquist. Sinusoidal signal at 1.3 times Nyquist before sampling into pixels.
